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[CDO] Prefetch policy [message #1841979]

Sat, 05 June 2021 15:36

Sorour Jahanbin

Messages: 2
Registered: May 2021

Junior Member

Hi,

I've just started working with CDO and I cloned code from the Git repository.
I have a question about prefetching and caching. I see that we can load objects on-demand using RevisionPrefetchingPolicy, CollectionLoadingPolicy and CDOFetchAnalyzer. But is it possible that we can load just the features of the object we need instead of the whole object?

For example:

Customer {
attr : name,
attr : address
}

for (Customer c : getCustomers()){
c.name.println();
}

Here, I just care about the name attribute of the Customer and there is no need to load the address as well.

Could you please let me know that CDO supports this? if yes, how (using which classes), I can implement this?

Thanks,
Sorour

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Re: [CDO] Prefetch policy [message #1842003 is a reply to message #1841979]

Mon, 07 June 2021 05:02

Eike Stepper

Messages: 6693
Registered: July 2009

Senior Member

Loading objects only partially is not supported. If this kind of performance tuning is essential for your use case you must design your model accordingly. E.g., factor the features that don't need to be loaded initially into a separate class /object.

Please be very careful with (ideally avoid) a CollectionLoadingPolicy. It's not compatible with many newer CDO features!

Cheers
/Eike

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